Measurements of dust particles entrained in flue gas are essential to the abatement strategy for air pollutions caused by stationary sources. The measuring method is prescribed in JIS Z 8808, and the owners of the facilities are obligated to measure their emissions in Japan.
Recently, new themes have attracted a big attention in the dust sampling field, such as the evaluation of the effects of anisokinetic sampling on the measurements, difficulty of isokinetic sampling procedure in the low gas-velocity range, and the conversion into the high-volume sampling method, because the emission level in stationary sources is getting relatively lower due to the strengthening the regulation and wide-rang adoption of high-performance dust collectors.
On the other hand a new concept is presented, that the condensible dust and mist particles should be estimated as particulate matters, especially in considering the contribution to the suspended particulate matter in environment, while a large part of these particles are vaporized and neglected by heating the samples collected on the filters at the temperature of 105-110°C or higher in the present measuring mannual.
The state of art on the techniques of the continuous measurement, the simple and rapid determination method and the measurement of particle size distribution are also briefly reviewed.

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Dispersion process of pollutants emitted from an offshore airport source has been analysed by using a puff model which may take into account the unsteady conditions around an offshore airport such as the interaction of land and sea breezes and moving aircraft sources.
A large number of field tracer experiments have been carried out around the site under costruction of the New Kansai Offshore Airport for two years since 1978 as one of the environmental impact assessments. In a previous paper (Ohkura and Nishi, J. Japan Soc. Air Pollut., 17 (3), 187-194 (1982)), the dispersion process for the low-level source in those experiments was investigated in detail, and the three-dimensional diffusion parameters as well as a few meteorological parameters applicable to the lower atmosphere above the sea were estimated with the optimization technique by matching the calculated concentrations with the observed ones at the observation stations situated near the shoreline.
In the present paper, the diffusion parameters are also obtained in a different way; applying Taylor's diffusion equation to wind turbulence data measured by means of a three-dimensional ultrasonic anemometer installed near the source. The so-called Hay-Pasquill time scale factors β relating Lagrangian and Eulerian scales of turbulence in the respective directions are closely related with the intensity of turbulence and determined by using again the optimization technique. Obtained three-dimensional diffusion parameters agree well with the estimated parameters. It is also shown that the calculated ground-level concentration distributions are in good agreement with the observed ones and the estimated values of β are within the range of the ones obtained in the other experimental and theoretical studies.

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A gas chromatographic determination method for alcohols at ppb levels has been developed based on the rapid formation of an alkyl nitrite in the heterogenous reaction of alcohols with NO₂ on cleaned Pyrex glass surface. Methyl and ethyl alcohols at several tens ppb and isopropyl alcohol at hundreds ppb were detected in the polluted air at the road sides. Methyl alcohol at several thousand ppb and ethyl n-propyl, isopropyl, isobutyl alcohols at hundreds ppb were detected in the exhaust gas from gasoline engines. Methyl and ethyl nitrites were formed in the dark or photochemical reaction of these alcohols with NO₂ in the exhaust gas.

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The effects of atmospheric environment on the growth of radish plants (Raphanus sativus L. cv. Comet) were evaluated by small open-top chambers. The experiments were conducted in the field of Tokyo University of Agriculture and Technology (Fuchu-city, Tokyo) from May to October in 1987.
Leaf area and dry weight of the plants in non-filtered treatment were significantly reduced compared with those of the plants in filtered treatment during the experimental periods in summer. In these experiments, visible injury of leaves was observed in non-filtered treatment. This visible in jury was similar to that caused by the exposure to O₃. Relative growth rate of plant dry weight and net assimilation rate of the plants in non-filtered treatment were reduced compared with those of the plants in filtered treatment. These results suggest that the efficiency of dry matter production is reduced by ambient O₃.
Leaf areal growth of cotyledon was reduced linearly with the increase of average 8-hrs (8:00-16:00) dose of O₃ during the experimental periods. It suggests that areal growth of cotyledon is very effective as a plant indicator in the evaluation of atmospheric environment by small open-top chambers.

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We developed a continuous method of mercury measurement in exhaust gas from stack. The outline of this method is as follows: after specified pre-treatment of using reducing agent (SnCl₂), sample gas is continuously introduced into analytical quartz cell and then analyzed by cold vapor atomic absorption technique. We investigated the accuracy of this method and the adaptation for thesample. gas from municipal refuse incinerator. The results were as follows.
1. The linearity was less than 2% till mercury concentration 3.0mg/m³ in case ofusing 10cm cell length.
2. 90% response time was about 20 second.
3. The influence by interference gases can be neglected.
4. Regression line between this continuous method (y) and wet absorption method (x) used KMnO4 and H₂SO₄ can be described as follows;
Y=1.08X+0.01.
The coefficient of correlation was 0.988. As a result of this studies, it became clear that this continuous method can be applied to measure mercury in exhaust gas.

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Basic experiments, on the high-volume air samplers were made to examine their sampling, weighing, locality of particulate sample on a filter, and the precision of elemental analysis.
After the calibration of a flow meter, instrumental errors of a high-volume air sampler could not be found at 5% level of significanc, and no significant difference caused by setting place of sampler could be also found.
In comparison with various filters, a collected amount of particulates on a “Polyfrone” filter was the least. And a slightly larger weight was obtained on a glass fiber filter. A membrane filter was concluded to be unsuitable for practical use because of its large weight change by humidity.
Localities of sample on a filter was seen in a high-volume air sampler without cyclone. In the case of a high-volume air sampler with cyclone, face density of sample at the center of filter was less than the around.
Applying to the receptor model, we found that the error of neutron activation analysis should be taken into account 20-50% for trace elements, which is not enough sensitivity, and 5-10% for ma jor elements or high sensitive elements.

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